Overview of ISS US Fire Detection and Suppression System · 6/25/01 Alana Whitaker 1 Overview of ISS US Fire Detection and Suppression System 6/25/01 Alana Whitaker 2 Outline Ł Intro

6/25/01 Alana Whitaker 1

Overview of ISS US Fire Detection and Suppression System


Outline

� Intro to Fire Detection and Suppression (FDS)

� Description of (FDS) Subsystems� Portable Fire Extinguishers (PFE)

� PFE Testing

� Smoke Detectors (SD)� Ventilation and Air Monitoring/Supply Systems

� Portable Breathing Apparatus (PBA)

� FDS System Component Location and Status

� FDS System Capabilities

Overview of ISS U.S. Fire Detection and Suppression System

Alana Whitaker

ISS ECLS Subsystem Manager Fire Detection and Suppression Systems

NASA Johnson Space Center

NASA/CP—2003-212103 49

https://ntrs.nasa.gov/search.jsp?R=20030053429 2019-08-21T00:10:37+00:00Z


Outline (cont.)

� FDS Automatic and Manual Response

� Post Fire Atmosphere Restoration and Air Quality Assessment

� FDS Research Needs


Intro to FDS on ISS

• Fire Detection and Suppression (FDS) includes:– Detection of smoke

– Isolation of fires

– The means to extinguish fires

– The means to recover from fires

NASA/CP—2003-212103 50


Portable Fire Extinguisher (PFE)

PFE w/Cover (config. on orbit) PFE w/o Cover


Portable Fire Extinguisher (PFE)� PFE Characteristics

� Contains 6 lbs CO2 at 850psi

� Discharges in 45 sec.

� Has two nozzles:� Conical Nozzle (open area nozzle) for

open area suppression

� Cylindrical Nozzle (closed volume nozzle) for suppression

in closeout fire ports

Open Area NozzleClosed Volume Nozzle

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PFE Cover� PFE Cover Characteristics

� Made of Nomex

� Fits snuggly to PFE

� Keeps PFE within allowable touch temp. limits during discharge (w/o Cover, PFE reaches 0 deg. F and nozzle -32

deg. F)


Fire Suppression Ports� 1� or 0.5� diameter perforated access

ports in racks and standoffs for the cylindrical nozzle (enclosed area nozzle) to suppress fires

� O2 concentration in a rack is reduced to < 10.5% within 1 min of suppression.

Suppression port nozzle inserted Suppression port nozzle inserted into suppression portinto suppression port

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Fire Suppression Testing

� Enclosed Volume Tests (cylindrical nozzle)� All CO2 sensors show > 50% concentration for

volumes 60ft3 or less

� Good mix in enclosed volumes

� Open Volume Tests (conical nozzle)� Fire is suppressed by a combination of blowing

the fire out (3 lb mass in first 10 sec) and supplying CO2.


Smoke Detector

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Smoke Detector

� Photoelectric Smoke Detector� Based on smoke particles scattering a light beam

� Light from a laser source is reflected by mirrors back to a photodiode (obscuration).

� Scattered light is measured by a second photodiode (scattering)

� Alarms are based on the voltage level generated by the scattering photodiode.


Smoke Detector Principle

Airflow

El ec tr onics

Photodiodes

Scatter Path

Obscur at i on Path

Laser Diode

NASA/CP—2003-212103 54


Smoke Detectors in Ventilation� Smoke Detectors are located on the ventilation filter intake ducts.

CROSSOVER DUCT

TRANSITION DUCT ASSEMBLY

PORT

STBD

OVERHEAD

SUPPLYDIFFUSER(6 POSITIONS)

BACTERIA FILTERASSEMBLY (6 POSITIONS)

CDRASUPPLY

IMVOUT

ARS RETURN

IMV IN

PERFORATED MANUALDAMPER VALVE

PERFORATED MANUALDAMPER VALVE

MANUAL DAMPER VALVE

MANUAL DAMPER VALVE

MANUAL DAMPER VALVE

DECK

SMOKE DETECTORLABPD1

SMOKE DETECTORLABSD5 8

8

Lab Cabin Air Temperature and Humidity Control Assembly with Smoke Detectors


Smoke Detectors in Ventilation

Smoke Detector

NASA/CP—2003-212103 55


Air Monitoring/Supply System� Air components/concentrations are monitored

by the Major Constituent Analyzer (MCA) in the LAB.� Air samples are taken from each module and

routed to the sensor (mass spec.) in the MCA.

� MCA gives percent compositions. (Typical O2

levels on ISS are slightly less than 24%.)

� Metabolic O2 and N2 are supplied from Orbiter, Service Module, and Progress


Total and Oxygen Partial Pressure ControlNot In Campout Mode

� Pressure control when Not in Campout Mode (nominal) is done with closed-loop control� Total Pressure

� The PCPs will be taking constant (1 Hz) total pressures

� If the total pressure drops below 14.25 psia the Nitrogen Isolation Valve in the primary PCP will open

� When the total pressure >= 14.3 psia the Nitrogen Isolation Valve in the primary PCP will close

� Oxygen Partial Pressure

� The MCA will be making constant readings of the Station atmosphere

� If the oxygen partial pressure drops below 3.00 psia the Oxygen Isolation Valve in the primary PCP will be opened

� When the oxygen partial pressure >= 3.05 psia the Oxygen Isolation Valve in the primary PCP will close

NASA/CP—2003-212103 56


Total and Oxygen Partial Pressure ControlIn Campout Mode

� While in Campout Mode, the ppO2 in the Airlock will be controlled by the following:

� If ppO2 < 2.7 psia in the Airlock, the Airlock PCA will open the PCP OIV for 4 minutes +/- 10 seconds

� If the ppO2 > 2.85 psia in the Airlock, the Airlock PCA will open the PCP NIV for 2 minutes +/- 2 seconds

� If either the PCP NIV or OIV was opened, wait 11 minutes after the valve closes

� Repeat

� Total pressure control is via manual operation of the Depress Pump

� The rest of Station will continue to control total and oxygen partial pressures in the standard method


Portable Breathing Apparatus (PBA)

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Portable Breathing Apparatus (PBA)

� PBA is composed of:� Mask

� 15 minute O2 bottle

� 30� hose

� Provides O2 to crew in emergency situations� Post-fire clean-up

� Environmental contamination

� Depressurization


FDS System Component Location

� Node 1 � 2 area Smoke Detectors (SD), 1 (PBA), 1 (PFE)� Currently on orbit

� PFE and PBA are nominal (have not been used)� SD#1 is powered, enabled, and nominal� SD#2 is powered and disabled

� Lab � 2 area SD, 2 system rack SD (AR rack, CHeCS rack), up to 13 experiment rack SD (3 experiment rack SD at 7A), 2 PBA, 2 PFE� Currently on orbit

� PFEs and PBAs are nominal (have not been used)� 4 SDs (2 area and 2 rack) are powered, enabled, and nominal� 1 payload SD is powered, enabled, and nominal� 2 payload SDs operate intermittently based on payload operations

NASA/CP—2003-212103 58



� A/L � 1 area SD, 1 duct SD, 2 Pre-breathe Hose Assemblies (PHA), 3 O2 bottles, 1 PHA spares kit, 1 PFE

� MPLM � 1 duct SD, 1 PFE, 1 PBA (PBA & PFE stored in Node1 when MPLM is not attached)



Suppression Port

Portable Fire Extinguisher

Smoke Detector

Portable Breathing Apparatus

Visual Indicator (LED)

ISPR FDS equipment required depends onpayload and payload rack integration. Theseschematics show worst case scenario untilpayload rack designs are finalized.

1

1

LAC6DDCUs

LAC5ISPR

LAS6Mod. Temp. TCS /Cabin Air Assembly

LAC4ISPR

LAC3ISPR

LAC2ISPR

LAC1ISPR

1

LAS5MSS / Avionics

LAS4ISPR

LAS3ISPR

LAS2ISPR

1

LAS1ISPR

LAF1Avionics #2

LAF2Avionics #3

LAF3ISPR (Window)

1

LAF4Fuel Cell Water Storage

LAF5Avionics #1 / Cond.

Water Storage

LAF6ARS

(CDRA, MCA, TCCS)

LAP6Low Temp. TCS /Cabin Air Assembly

1

LAP5MSS / Avionics

LAP4ISPR

LAP3FSS / Stowage

LAP2ISPR

1

LAP1ISPR

F Node 2

A

1

Node 1

X4

X1

X2

1

X3

1

1

1 1 1

P Z

N S

A

F

N1ZStowage 1

PMA - 1

N1NStowage 2

N1SStowage 4

N1PStowage 3

Lab

Zenith Truss Cupola

Airlock Node 3

P Node 1

Equipment Lock

Crew Lock

AF1Avionics

AA1Cabin Air Assembly

Airlock

LABNode1

NASA/CP—2003-212103 59


FDS System Capabilities

� Node 1, Lab, A/L, & MPLM FDS� Fire emergency alarm received if any single SD

FIRE status flag is set equal to �FIRE� � Scatter must exceed the fire threshold two

consecutive times, the detector then initiates an active Built In Test (BIT), and the scatter must still be exceeding the threshold after the BIT to set the status flag equal to �FIRE.�

� Location may be determined by laptop.


FDS Automatic and Manual Response(Overview)

� In case of fire or smoke� The crew can manually push the fire alarm or the

Smoke Detectors can automatically initiate the fire alarm to perform the following functions:

1) Remove power to racks-to isolate ignition sources

2) Isolate module by shutting off ventilation (close IMVvalves, sample delivery systems, cabin fans)-to stop air flow within module and exchange between modules

3) Inhibit introduction of O2 and N2 into module (inhibit pressure control assembly in LAB)

*Crew can use PFE at their discretion*

NASA/CP—2003-212103 60


Post Fire Atmosphere Restoration� Gaseous Contaminants removed by the following:

� SM - Micropurification Unit(БМП)� Removes 19 different gaseous contaminants using a catalytic

oxidizer (ambient) and expendable & regenerative charcoal beds.

� FGB - Harmful Impurities Filter (ФВП)� Removes gaseous trace impurities (particles of 0.5 to 300µm

to a level of 0.15 mg/m3).

� Lab - Trace Contaminant Control Subsystem (TCCS)

� Removes gaseous contaminants using a catalytic oxidizer (400ºC) and expendable sorbent and charcoal beds. Sorbent contains LiOH which can remove acid gases.


Post Fire Atmosphere Restoration� Carbon Dioxide Removal Assembly (CDRA)

� Removes CO2 from the atmosphere that was discharged from the PFE

� Extra charcoal air filters� Scrub the environment and contain 2% Pt for CO removal.

� CO2 Removal Kit (CRK)� Consists of a portable fan assembly with a LiOH cartridge

adapter.� Can be used with LiOH or ATCO catalyst canister for CO2 or

CO removal

� Venting module to space� Only in worst case scenario

NASA/CP—2003-212103 61


Post Fire Air Quality Assessment

� Air quality analysis done with the following equipment:� Compound-Specific Analyzer for Combustion Products

(CSA-CP)

� Carbon Dioxide Monitoring Kit (CDMK)

� Final analysis using Draeger detector tubes

� Atmospheric sampling, using GSC and AK-1 air sampling assemblies, for delivery to ground.


FDS Research Needs� Data to support suppressant selection

� Suppressant� Effective

� Not harm ECLSS or other equipment

� No/low toxicity

� Not require extensive clean up

� Microgravity research on suppression of fire� Experiments needed on fabrics and items on orbit likely

to burn

NASA/CP—2003-212103 62


??Questions??

Contact Info.

Alana Whitaker - NASA/JSC

ISS ECLS Subsystem Manager

Fire Detection and Suppression Systems

NASA/CP—2003-212103 63

Overview of ISS US Fire Detection and Suppression System · 6/25/01 Alana Whitaker 1 Overview of ISS US Fire Detection and Suppression System 6/25/01 Alana Whitaker 2 Outline Ł Intro

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